Dear Kenneth,
> Is the verb spelled nun hay hay "to wail" a geminate verb?
Yes. A verb with the last two letters the same is
by definition geminate. "Geminate" comes from the
same root as Latin geminus, or "twin" (think of
the constellation Gemini).
> Could it be
> conjugated using just nun and hay?
HH: No, Hebrew verbs are at least triliteral.
Yours,
Harold Holmyard